HCPCS Code A9278: External CGM receiver billing guide 2026

Key Takeaways

HCPCS Code A9278 describes an external receiver (monitor) for use with a non-durable medical equipment interstitial continuous glucose monitoring system, effective January 1, 2008.

Effective April 1, 2022, A9278 is invalid for Medicare billing of adjunctive CGM receivers; replacement code E2102 must be used for those claims instead.

A9278 remains active for TRICARE, VA, and state Medicaid programs (including New York eMedNY), and for any CGM system that fails to meet Medicare’s DME benefit criteria.

Pabau’s claims management software helps billing teams track active versus retired HCPCS codes and reduce CGM-related claim denials.

According to the Centers for Medicare and Medicaid Services (CMS) HCPCS Level II system, HCPCS Code A9278 carries the official descriptor: Receiver (monitor); external, for use with non-durable medical equipment interstitial continuous glucose monitoring system. The code has been active since January 1, 2008, and remains on the 2026 HCPCS code file as an active code for non-Medicare payers and specific Medicare use cases.

A9278 describes only the external receiver component of a CGM system, not the sensor or transmitter. A CGM receiver is the handheld or wearable display device that receives glucose data transmitted from a subcutaneous sensor via an external transmitter.

For the code to apply, the underlying CGM system must be classified as non-durable medical equipment (non-DME). That classification is what separates A9278 from the Medicare DME benefit pathway and from the adjunctive CGM receiver code E2102.

Billing staff at practices using claims management software should note that A9278 sits in the HCPCS A-code range alongside related CGM supply codes. For broader context on how HCPCS codes are structured across care settings, the HCPCS Code S9379 home infusion therapy billing guide illustrates similar non-DME supply coding logic. The code is classified as a miscellaneous supply and does not carry a national Medicare fee schedule rate under the standard DME PPS pathway.

HCPCS Code A9278 quick reference

Use the table below for a fast overview of A9278 before diving into payer-specific rules.

The CGM code family: A9276, A9277, and A9278

Continuous glucose monitoring systems involve three distinct hardware components, and HCPCS assigns a separate code to each. Getting all three right on a single claim prevents unbundling errors and ensures each component is reimbursed under the correct benefit category.

• A9276 describes the disposable subcutaneous sensor inserted under the skin to measure interstitial glucose levels. Each sensor unit covers one day of supply. The code is reported per unit per day of use.
• A9277 describes the external transmitter, the device that wirelessly relays sensor data from beneath the skin to the external receiver or display. Transmitters are typically reusable for months before replacement.
• A9278 describes the external receiver or monitor, the display device that receives transmitted glucose readings and shows trend data. For weight loss and diabetes care practices, correctly coding the receiver separately from the transmitter is the step most commonly bundled incorrectly. Related supply coding challenges appear in the HCPCS Code E0443 portable oxygen contents billing guide, which covers similar component-level DME claim construction.

A fourth related code, A9279, covers monitoring features or devices not otherwise classified (NOC). The VA fee schedule places A9279 at $85.97, significantly below A9278’s $1,872.21 rate, so correct component-level coding has material reimbursement implications.

Noridian Healthcare Solutions (the JD DME MAC) and Palmetto GBA’s PDAC published retired advisory articles specifying that stand-alone CGM systems should be billed with A9276, A9277, and A9278 as separate line items. While those articles have since been retired, the underlying component-coding logic remains the framework used by TRICARE and state Medicaid programs.

Documentation requirements for accurate CGM billing

Underdocumented CGM claims are a leading cause of post-payment audits for DME suppliers and diabetes care practices. The documentation burden for A9278 mirrors the requirements for the broader CGM supply set, and missing records at the point of care create downstream billing problems that are expensive to correct.

Prescription and order requirements

A valid physician or qualified non-physician practitioner order is required before a CGM receiver can be dispensed and billed. The order must specify the CGM system by type (adjunctive or therapeutic), confirm the patient’s diagnosis (typically a diabetes ICD-10 code such as E11.65 for Type 2 diabetes with hyperglycemia, or E10.65 for Type 1), and indicate medical necessity.

For HIPAA-compliant documentation around device prescriptions, practices should retain signed orders in the patient record prior to claim submission. Teams managing overlapping supply billing can also benefit from reviewing the HCPCS Code A5500 diabetic depth-inlay shoe billing guide to see how CMS applies medical necessity documentation standards across diabetes-related DME codes.

Medical necessity documentation

For non-Medicare payers billing A9278, the patient chart should contain evidence that the CGM system does not qualify as durable medical equipment under the applicable payer’s benefit definition. This typically means documenting that the device does not meet the local coverage determination (LCD) criteria for therapeutic CGM under Medicare DME, or that the payer’s own benefit structure places CGM supply in a non-DME category.

Relevant clinical documentation to retain includes: the ordering provider’s notes confirming diabetes diagnosis, the patient’s current glucose management regimen, prior glucose log data if the payer requires it, and a written acknowledgment of the CGM system’s classification.

Some state Medicaid programs, including New York’s eMedNY, issued specific 2023 guidance stating that A9276, A9277, and A9278 should be used for CGM systems that do not meet DME criteria, so payer-specific instructions may spell out exactly what clinical notes are required.

Consulting diagnostic coding documentation frameworks from adjacent specialty areas — such as the CPT Code 80307 presumptive drug test billing guide — can help billing teams build consistent documentation checklists across code sets.

Delivery and supplier documentation

For DME suppliers dispensing CGM receivers, proof of delivery records must accompany the claim file. For non-DME CGM systems billed under A9278, the delivery documentation requirement may be relaxed depending on the payer, but maintaining a dispensing record protects against retrospective audits. Date of service should align with the date the receiver was physically provided to the patient.

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Payer-specific billing rules and reimbursement rates

A9278’s validity and reimbursement pathway differ significantly across payers. Applying Medicare rules universally to this code produces errors on TRICARE, VA, and Medicaid claims.

Medicare

CMS Policy Article A52464 (Medicare Coverage Database) specifies the exact dates of service for which A9278 applies under Medicare:

• Before April 1, 2022: A9278 was valid for billing adjunctive CGM receivers to Medicare.
• April 1, 2022 to December 31, 2022: A9278 is invalid for Medicare adjunctive CGM receiver billing. E2102 must be used for those claims during this window.
• Any date of service (before and after April 1, 2022): A9278 remains valid under Medicare to describe any CGM system that fails to meet the DME benefit criteria — i.e., systems that do not qualify for coverage under the adjunctive or therapeutic CGM DME LCD. The April 2022 change only restricts A9278 for DME-qualifying adjunctive CGM receiver claims; non-DME CGM receivers continue to be reported with A9278 regardless of date of service.

In practice: if a patient’s CGM system qualifies as a therapeutic CGM under Medicare’s DME benefit, bill E2102 for the receiver. If the system does not meet DME criteria, A9278 remains the correct code under Medicare for those claims on or after January 1, 2023. Consult the CMS Physician Fee Schedule lookup for current locality-specific payment rates.

TRICARE / Humana Military

TRICARE clinical policy document CGM_MP23-034E, administered by Humana Military, requires that CGM supplies be reported using HCPCS codes A9276, A9277, and A9278. Unlike Medicare, TRICARE has not transitioned away from A9278 for CGM receiver billing.

Practices billing TRICARE for CGM systems should continue using the three-code set unless a subsequent TRICARE policy update changes this requirement. Always verify with the current Humana Military provider portal before submission.

VA Community Care

The Department of Veterans Affairs Community Care program’s Outpatient Data Tables (v3-25, Table K) list A9278 (External Receiver, CGM Sys) at a rate of $1,872.21. This is one of the few published fee schedule rates for this code and provides a useful benchmark, though VA rates are specific to the Community Care fee schedule and do not apply to Medicare or commercial payers.

State Medicaid

State Medicaid programs follow their own CGM coding guidance. New York’s eMedNY issued a January 13, 2023 coding change communication specifying that A9276, A9277, and A9278 should be used for CGM systems that do not meet DME criteria.

This mirrors the post-2022 Medicare framework but is a separate, state-specific policy. Practices billing multiple state Medicaid programs should verify CGM coding guidance from each state’s provider manual, as rules vary. Verify current rates via your payer’s provider portal or billing reference.

A9278 vs E2102: What changed in April 2022

The April 1, 2022 change is the single most consequential update in A9278’s history. It produced two distinct billing errors: using A9278 for Medicare adjunctive CGM claims, and using E2102 for non-DME CGM claims where A9278 still applies.

What E2102 describes

CMS Transmittal R11292CP added E2102 to the HCPCS file effective April 1, 2022. The official descriptor for E2102 is: Receiver (monitor); adjunctive, for use with adjunctive continuous glucose monitor (CGM) or adjunctive CGM component of an insulin pump.

This code was added to describe the use of an insulin pump with an integrated adjunctive CGM receiver function, as well as standalone adjunctive CGM receivers billed under Medicare’s DME benefit. The key distinction is that E2102 is the Medicare DME pathway code. A9278 covers the non-DME pathway.

Adjunctive vs therapeutic CGM

These two clinical categories drive which code set applies:

• Adjunctive CGM is used alongside traditional blood glucose monitoring (BGM). The CGM data supplements rather than replaces fingerstick readings for insulin dosing decisions. A9278 (non-DME) and E2102 (Medicare DME) both apply to adjunctive CGM systems, depending on whether the device qualifies under the DME benefit.
• Therapeutic CGM is used as a replacement for fingerstick testing. These devices are covered under a separate Medicare LCD for therapeutic CGM (durable, prescribed devices meeting specific clinical criteria). Therapeutic CGM receivers are typically billed under the DME fee schedule using the appropriate K-code, not A9278 or E2102.

Misclassifying a therapeutic CGM as adjunctive (or vice versa) generates both a coding error and a potential compliance issue. The clinical record must clearly support whichever classification is used. Verify that the ICD-10 diagnosis codes on the claim support the CGM classification being billed.

For additional HCPCS lookup support, consider verifying code descriptions and related crosswalk data via the NLM Clinical Tables HCPCS API for programmatic lookups.

Charge master update checklist

For billing teams updating charge masters to reflect the A9278/E2102 transition, work through these steps:

1. Identify all active CGM receiver line items currently mapped to A9278.
2. Determine whether the associated CGM system qualifies as adjunctive DME under Medicare’s LCD.
3. For adjunctive DME CGM systems billed to Medicare: remap those line items to E2102.
4. For non-DME CGM systems billed to Medicare (on or after January 1, 2023): retain A9278.
5. For TRICARE and applicable state Medicaid programs: retain A9278 unless that payer’s current guidance specifies otherwise.
6. Document the update date, the payer affected, and the clinical rationale in the charge master change log.

Use the NLM Clinical Table Search API for programmatic HCPCS code verification if your practice management system supports API-based code lookups.

Conclusion

HCPCS Code A9278 remains active and required for TRICARE, VA, and non-DME Medicare CGM claims. One rule change drives the confusion: Medicare’s April 2022 invalidation of A9278 for adjunctive CGM receiver billing, replaced by E2102. Treating the code as universally obsolete forfeits reimbursement on legitimate non-DME claims; ignoring the change produces ongoing Medicare denials.

For functional medicine and chronic disease practices managing ongoing CGM supply billing, a structured approach to payer-specific code mapping reduces claim holds and denials. Pabau’s claims management software helps practices maintain accurate charge master mappings, flag payer-specific rules, and reduce the manual errors that drive CGM claim denials. To see how Pabau’s claims management software flags payer-specific CGM rules and cuts denials, book a demo.

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